Patent GB-527619-A (GB)
Title: Abrading apparatus
IPC: B24C5/06
Filed: 1939-06-13
Abstract: 527,619. Sand-blasting apparatus. TRIGGS, W. W. (Pangborn Corporation). June 13, 1939, No. 17237. [Class 60] A centrifugal sand-blasting apparatus of the kind having a rotor with radial blades terminating short of the axis so as to leave a central opening containing a cup rotating with the rotor and supplied with abrasive from a spout, has a non-rotary deflector within the cup provided with a helical blade for directing the abrasive over the edge of the cup, to be picked up by the blades of the rotor. In one form a rotor R, Fig. 1, has radial blades 15 secured within dovetailed slots between plates 12 by blocks 17, Fig. 2, and has a cup 28 attached to the rotor shaft 11 by a screw 27. The cup is provided with radial ribs 31 and grooves 29 to cause a laver of abrasive to be carried round therewith and pile up at an angle indicated at 62, the abrasive being supplied by a stationary spout 35. A deflector 67 has a flared mouth 38 to direct abrasives from the spout to,the interior of the cup and is secured by a flange 41 to a support 43 angularly adjustable on a stationary casing 45 by means of bolts and arcuate slots 48. The helical blade 63, Fig. 6, of the deflector engages the surface of the piled-up abrasive in the cup and directs it over the edge 33 thereof, the edge 64 of the blade being inclined at the piling angle so that little wear takes place. A non-helical flange 67 on the deflector prevents abrasive from being discharged from the cup except through a gap 69 between the flanges 63, 67 and this determines the position 71 Fig. 2, at which abrasive is delivered to the rotor, the position being adjustable by the support 43. The abrasive at 71 is travelling at approximately the speed of the blades 15 and the latter deliver it at 72 with a higher speed. To restrict the width of the band of abrasive delivered, an arcuate guide 77, Fig. 8, may be attached to the support 43 to deflect abrasive 81 into the main stream 79 and the flange 67 of the deflector may be located inside the edge 33 of the cup. The rotor blades 15 may be provided with one or more longitudinal ribs 91, Fig. 12, to prevent axial movement of the abrasive after it has left the cup 28. In a modified form of cup, notches 97, Fig. 14, are provided in the edge 33 and are located forwardly of the blades in the direction of rotation so that separate jets of abrasive will be delivered to the blades 15, and in another modification the cup 115, Fig. 18, is closed at the end and has slots 123 in its periphery for delivering jets of abrasive, by means of the helical deflector 122, in advance of each blade 15. The spout 121 may be integral with the cup 115 or separate to allow angular adjustment of the latter. In another form of apparatus the cup 103, Fig. 15, is located on the other side of the medial plane of the blades 15 and discharges abrasive from the edge 33b by means of the deflector 63a attached at 107 to the feed spout 105. The deflector and spout may be angularly adjustable together, or the former only may be adjustable. The cup is attached to the rotor R by means of studs-110 or may be attached to the blades 15, and the centre of the rotor may be closed by a wear plate 101. In a modification of this form, the cup 135, Fig 21, is attached to the rotor R by means of a central shaft 134 and discharges abrasive over the edge 33c. The deflector 153 is attached by its flange to lugs 143 on a support 144 secured to the casing 45 by angularly adjustable bolts and arcuate slots, and a guide plate 155, similar to that shown in Fig. 8, may be attached to one of the lugs 143. Any of the open-ended cups may have a notched edge as shown in Fig. 14. Specification 518,183 is referred to.